1. Field of the Invention
Embodiments of the invention relate generally to amphibious vehicles and, more particularly, to land-based vehicles adapted for amphibious use. Still more particularly, embodiments of the invention relate to a tracking system for adapting a land-based vehicle for use in marshy or swampy terrain.
2. Description of Related Art
Amphibious vehicles, known as marsh buggies, were first developed to support oil and gas exploration operations conducted in marshy or swampy terrain. Since their development, there has been growing concern in regards to the environmental impact of operations in marshlands, wetlands, and other low-lying areas due, at least in part, to the deterioration of many marshland and wetland areas. In response, significant efforts are being made to preserve, protect and restore these areas. Marsh buggies are currently being used to assist in these restoration and preservation efforts.
Marsh buggies typically include a pair of pontoons connected to a center platform. The pontoons are usually surrounded by a cleated track system that is capable of engaging ground or swamp land to propel the vehicle. The track system uses one or more endless chains surrounding the periphery of each pontoon. The endless chains, supporting the cleated tracks, are driven about the periphery of the pontoons, by a sprocket or other means, in order to provide propulsion to the vehicle. By varying the track speed around each pontoon, the vehicle can be advanced, turned, or reversed.
Due to their cleated track system, marsh buggies are ideal for operation in wetlands, marshlands, and other low-lying areas. Moreover, many have been adapted to haul personnel and cargo as well as serve as the operating platform for various types of equipment, such as excavators, draglines, and backhoes. Typically, the top several inches of the ground in wetlands, marshlands, and other low-lying areas are mud or soft terrain that cannot support weight. However, beneath the mud or soft terrain, there is solid ground that can support weight. During operation of a marsh buggy, the cleated tracks surrounding each pontoon sink into the soft terrain, or mud, until the tracks contact the solid ground beneath. Contact between the cleated tracks and the solid ground provides traction for the marsh buggy, allowing the marsh buggy to maneuver through the mud or soft terrain.
Additionally, marsh buggies are often capable of floating in order to navigate small bodies of water due to the buoyancy provided by their pontoons. However, these vehicles are not designed to operate while floating. Thus, marsh buggies are limited to performing earth-moving operations on dry land or in water where their pontoons remain in contact with the ground.
Most conventional marsh buggies and amphibious vehicles are manufactured and sold as “turnkey” vehicles. In other words, such marsh buggies are each sold as one complete, integral vehicle including the pontoons, cleated tracks, drive train, chassis, engine, platform or cabin, etc. Consequently, such conventional marsh buggies tend to be relatively expensive and intended for a single purpose—swamp and wetland traversal. In addition, many conventional marsh buggies are designed for construction and/or excavation activities in marsh or wetlands, and thus, are typically relatively large and robust. As a result, these conventional amphibious vehicles typically have a large footprint, which may be of concern in environmentally sensitive areas. Further, the overall size of such conventional amphibious vehicles may restrict and/or limit their use in narrow passages and/or close-quarters projects.
Accordingly, there remains a need for an amphibious vehicle capable of accessing and/or navigating through tight passages, while having a footprint that lessens or minimizes the impact of the vehicle on the environment. Therefore, embodiments of the invention are directed to an amphibious vehicle that satisfies this need and seeks to overcome limitations of the prior art.